I tried at the conference to get people to agree that hotswap (i.e. reloading classes in a running system) was something that the JVM needed to add, so that the 99.9% of JVM users programming in Java can have a more dynamic programming experience. It really matters when it's there (especially for people that develop server software, which is a large part of the Java community), and there's a real, ingenious solution already implemented as part of the MLVM project that works well enough for me to use in development all-day every day.

When I brought it up during this discussion, I got nowhere, and people basically looked at me like I was an idiot. It was pretty disappointing to see that a room full of language guys just didn't care about anything that would improve Java itself; the discussion pretty much entirely focused around small-scale stuff that would make it easier to efficiently implement dynamic languages on the JVM.